GIA: "OBSERVATIONS OF OVAL-, PEAR-, AND MARQUISE-SHAPED DIAMONDS: IMPLICATIONS FOR FANCY CUT GRADING".

Digital Report - immediate delivery to your email. Date of Publishing: 2024.No. of Pages: 25. A cut grading system useful at all levels of the diamond trade must encompass the visual appeal of polished diamonds. This paper presents results from observations of oval-, pear-, and marquise-shaped diamonds for face up appearance and outline appeal. In a controlled environment, an international cross section of diamond buyers, sellers, cutters, and appraisers observed sets of research diamonds in each shape; internal observation teams also examined diamonds submitted to GIA for grading services. Observers consistently disliked diamonds with prominent windowing but showed a broader range of opinions regarding the “bow tie” and “crushed ice” patterns typically found in these rounded fancy shapes. The distribution of opinions indicates significant differences in both regional preferences and personal taste for certain outlines and appearance patterns. Virtual facet maps, calculated from the th